This application claims the priority of commonly owned German patent application Serial No. 199 46 932.6 filed Sep. 30, 1999. The disclosure of the above-referenced German patent application, as well as that of each U.S. and foreign patent and patent application mentioned in the specification of the present application, is incorporated herein by reference.
The invention relates to improvements in methods of and in apparatus for testing successive commodities (such as box-shaped containers, especially so-called packets containing smokers"" products) of short or long series of such commodities. For example, the testing apparatus of the present invention can be utilized in a production line which turns out so-called soft packets or so-called hinged-lid packets of plain or filter cigarettes. More specifically, the invention relates to improvements in methods of and in apparatus for ascertaining the outlines or shapes of cigarette packets or analogous commodities and for ascertaining the presence or absence of departures of the outlines of successive commodities from a predetermined (desirable or optimum) outlines.
It is customary to make the envelopes of cigarette packets from several layers including a cardboard layer, at least one paper layer, at least one metallic layer (such as a layer made of tinfoil or aluminum foil), and an outermost layer of transparent or translucent plastic material. One or more layers are normally obtained by draping a prefabricated blank around the array of cigarettes or around a finished inner envelope; this results in the development of flaps, tucks, panels and/or other projecting parts which are normally glued or heat-sealed to the adjacent layer of the respective converted blank. It happens, from time to time, that the projecting parts are not glued, or are not adequately glued, to the adjacent portions of the respective converted blanks, and this can cause problems, for example, if an array of say ten cigarette packets is to be introduced into a so-called carton.
It also happens at times that a flap or tuck or panel is not properly positioned relative to the neighboring part or parts of an envelope forming part of a cigarette packet or an analogous commodity, i.e., the panel, tuck or flap can be glued to the adjacent part of an envelope but not in proper position so that a portion thereof projects beyond the outline of the packet. This detracts from the appearance of the finished packet. Still further, it is desirable to ensure that the revenue label and/or an adhesive-coated finished patch or stamp be properly applied to a selected side (such as the underside) of the finished cigarette packet.
The monitoring of successive packets of cigarettes or other smokers"" products must be carried out at a high frequency because a modern production line normally turns out huge quantities of plain or filter cigarettes, cigars, cigarillos or other rod-shaped smokers"" products. Moreover, the testing of successive packets to determine the presence or absence of one or more flaps, panels, tucks, labels, stamps or like which protrude beyond the prescribed outline of the commodity must be carried out with a high degree of reliability, i.e., each commodity which does not exhibit a desired or required outline must be segregated from other commodities without fail even if such testing must be carried at a high or very high frequency.
An object of the present invention is to provide a novel and improved method of monitoring block-shaped or other types of commodities, such as cigarette packets, for the presence or absence of protruding panels, flaps, tucks, stamps, labels and/or other sheet-like parts.
Another object of the invention is to provide a method which can be practiced to simultaneously monitor successive commodities from several sides or directions so that eventually existing protruding flaps or the like and/or other deformities of the commodities which cannot be detected during an examination of a single side are, or are more likely to be, detected in accordance with the improved method.
A further object of the invention is to provide a method which involves gentle treatment of successive commodities so that the practice of the method does not entail any damage to (such as defacing or deformation of) the tested commodities.
An additional object of the present invention is to provide a novel and improved apparatus for the practice of the above outlined method.
Still another object of the invention is to provide an apparatus which is capable of carrying out a plurality of simultaneous tests and which can segregate (preferably automatically) defective commodities from satisfactory commodities.
A further object of the invention is to provide an apparatus which can be utilized with particular advantage in production lines which are designed to turn out soft or hinged-lid packets of plain or filter cigarettes or other rod-shaped smokers"" products.
Another object of the invention is to provide a novel and improved circuitry which can be utilized in the above outlined apparatus.
One feature of the present invention resides in the provision of a method of ascertaining the presence or absence of departures or deviations of the outlines or contours or shapes of successive normally identical commodities from a predetermined outline, contour or shape (hereinafter referred to as outline). For example, the commodities can constitute containers (such as rectangular parallelepipeds typical examples of which are packets containing arrays of rod-shaped smokers"" products). The method comprises the steps of advancing successive commodities of a short or long or continuous series of equidistant or randomly spaced-apart commodities along a predetermined path (e.g., by the horizontal upper reach or stretch of an endless belt, band or chain conveyor) in a predetermined direction, establishing at least one curtain of radiation (e.g., a vertical curtain of radiation which propagates itself downwardly) across a predetermined portion of the path so that successive commodities advancing along the aforementioned portion of the path intercept amounts of radiation commensurate with (i.e., reflecting or indicative of) their outlines, and removing from the path each commodity which intercepts an amount of radiation departing from a predetermined amount which is indicative of the aforementioned predetermined outline (such as the outline of a commodity or prototype having an ideal or desired or optimum outline).
In accordance with a presently preferred embodiment of the method, the removing step includes generating first signals (such as electric signals) which denote the amounts of radiation intercepted by successive commodities during advancement along the predetermined portion of the path (such signals are indicative of the actual or ascertained outlines of the respective commodities), generating a reference signal which denotes the amount of radiation intercepted by a commodity (such as the aforementioned prototype) having the predetermined outline, and comparing each first signal with the reference signal to thus ascertain the extent of deviation of the first signal from the reference signal, i.e., to ascertain the extent of deviation of the outlines of successively monitored commodities from an ideal or optimum outline.
The establishing step can include establishing or providing a single curtain or a plurality of discrete curtains, for example, two coplanar curtains having identical or different widths. Each of the plurality of (e.g., two) discrete curtains preferably extends across the predetermined portion of the path in a position such that it is at least partially intercepted by successive commodities having the predetermined outline (provided, of course, that the commodities are properly oriented during advancement along the predetermined portion of the path, e.g., that successive commodities form a row or file of commodities having identical orientations relative to the advancing means).
As already mentioned hereinbefore, the advancing step can include moving successive commodities along an at least substantially horizontal path, and the at least one curtain (or two or more coplanar curtains) can be located in an at least substantially vertical plane crossing the predetermined portion of the path.
If the commodities are containers (such as packets for arrays of plain or filter cigarettes), they can include portions (such as panels, flaps, tucks, labels and/or stamps) which assume first positions when the outlines of such commodities at least approximate the predetermined outline (normally, such portions lie flat against the adjacent portions of the container). However, such portions of the containers assume second positions (e.g., they can extend away from the adjacent portions of the container) when the outlines of the commodities (contaners) depart from the predetermined or optimal outline. Such improper positioning of portions of the containers can be attributable to the application of insufficient quantities of glue, to non-uniform application of glue, to insufficient heating or cooling (i.e., to inadequate setting) of the glue, to improper creasing of the blanks of which the layers of the containers are made and/or to other defects of the blanks and/or improper manipulation of the blanks.
In addition to the basic (advancing, curtain establishing and removing) steps, the improved method can further comprise the steps of ascertaining the amounts of radiation intercepted by successive commodities in the predetermined portion of the path, generating first signals denoting the intercepted amounts of radiation, and comparing the first signals with a reference signal denoting the predetermined amount of radiation. The removing step of such method can include diverting from the predetermined path those commodities which, during advancement along the predetermined portion of the path, initiate the generation of first signals departing from the reference signal.
The establishing step of such method can include establishing a plurality of discrete curtains each of which extends across the predetermined portion of the path in a position such that it is at least partially intercepted by successive commodities having an outline at least approximating the predetermined outline. In accordance with such method, each of the first signals denotes the sum of radiations intercepted by the respective commodities advancing along the predetermined portion of the path.
The improved apparatus is designed to practice the above outlined method, i.e., to ascertain the presence and absence of departures of the outlines of commodities from a predetermined outline. The apparatus comprises means (such as an endless belt, band or chain conveyor) for advancing successive commodities along a predetermined path (e.g., an at least substantially horizontal path), means for establishing at least one curtain of radiation (e.g., a curtain which is disposed in a vertical plane) across a predetermined portion of the path so that successive commodities which advance along the predetermined portion of the path intercept amounts of radiation commensurate with (i.e., indicative of) their outlines, and means for comparing the intercepted amounts of radiation with a predetermined amount denoting the amount which would be intercepted by a prototype commodity having an outline at least approximating the predetermined outline.
The means for establishing at least one curtain of radiation can comprise at least one source of radiation (such as a light source) at one side of the predetermined portion of the path, and the means for comparing can comprise at least one receiver of radiation at another side of the predetermined portion of the path at least substantially opposite the one side.
More specifically, the means for comparing can comprise means for generating successive first signals having characteristics (such as intensities) denoting the amounts of radiation intercepted by successive commodities advancing along the predetermined portion of the path, means for establishing and maintaining a reference signal having characteristics which are indicative of the amount of radiation which is intercepted or which would be intercepted by the prototype commodity, and means for generating third signals which denote differences between successive first signals and the reference signal. The apparatus preferably further comprises means for (preferably automatically) removing from the predetermined path those commodities which initiate the generation of third signals denoting differences (between first signals and the reference signal) which are outside of a predetermined range of (acceptable) differences.
The signals are or can be electric signals.
The means for establishing at least one curtain of radiation can include a single radiation source which is arranged to emit a single curtain of radiation; the width of such single curtain can equal or exceed the width of the path and should exceed the width of the prototype commodity.
The means for establishing at least one curtain of radiation can include a plurality of radiation sources which are disposed at one side of the predetermined portion of the path and are arranged to establish discrete parallel (preferably coplanar) curtains of radiation, and such apparatus preferably comprises a plurality of receivers of radiation (one for each source) disposed at another side of the predetermined portion of the path opposite the one side. If the path is a substantially horizontal linear path, the radiation sources can be disposed at a level above the predetermined portion of the path and the receivers are or can be disposed at a level below such predetermined portion of the path.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved apparatus itself, however, both as to its construction and the modes of assembling and utilizing the same, together with numerous additional important and advantageous features and attributes thereof, will be best understood upon perusal of the following detailed description of certain presently preferred specific embodiments with reference to the accompanying drawings.